2698-65-9Relevant articles and documents
Photogeneration of a phosphonium alkylidene olefin metathesis catalyst
Khalimon, Andrey Y.,Leitao, Erin M.,Piers, Warren E.
, p. 5634 - 5637,4 (2012)
Treatment of ruthenium carbide (H2IMes)(Cl)2(PCy 3)RuC (1) with the photoacid generator (PAG) [Ph3S][OTf] (3) under 254 nm light results in a highly efficient catalyst for ring-closing metathesis (RCM) and ring-opening metathesis polymerization (ROMP) reactions. The reactions proceed via formation of the ruthenium phosphonium alkylidene complex [(H2IMes)(Cl)2Ru=C(H)PCy3][OTf] as the active catalytic species. In the case of ROMP of cycloalkenes, reactions do not require addition of PAG and protonation of 1 proceeds via allylic C-H bond activation of the substrate under UV light.
COMPOUNDS FOR SELECTIVE BINDING TO ESTROGEN RECEPTORS ALPHA/BETA RELATIVE TO GPER/GPR30
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Page/Page column 44, (2021/03/05)
The current invention is in the field of molecular biology/pharmacology and provides novel 3-oxabicyclo [3.3.1] nonene compounds and derivatives that modulate the effects of the classical estrogen receptors alpha and beta (ERalpha and ERbeta) with little to no biological or physiological effects on the G protein-coupled estrogen receptor GPER (also known as GPR30). These compounds may function as agonists and/or antagonists of one or more of the disclosed classical estrogen receptors.
Catalytic intramolecular carbonyl-ene reaction with ketones: Evidence for a retro-ene process
Tremel,Iacobucci,Massi,Olivero,Gal,Du?ach
, p. 7453 - 7458 (2015/09/02)
The ene-process with unsaturated ketones was catalyzed by Lewis acids such as bismuth or indium triflates. Unlike aldehydes, the reverse ene-process occurs with ketones, resulting in incomplete conversions, as shown by control experiments and analysis by ESI-MS.
Fast olefin metathesis at low catalyst loading
Peeck, Lars H.,Savka, Roman D.,Plenio, Herbert
, p. 12845 - 12853 (2012/11/06)
Reactions of the Grubbs 3rd generation complexes [RuCl2(NHC) (Ind)(Py)] (N-heterocyclic carbene (NHC)=1,3-bis(2,4,6- trimethylphenylimidazolin)-2-ylidene (SIMes), 1,3-bis(2,6- diisopropylphenylimidazolin)-2-ylidene (SIPr), or 1,3-bis(2,6- diisopropylphenylimidazol)-2-ylidene (IPr); Ind=3-phenylindenylid-1-ene, Py=pyridine) with 2-ethenyl-N-alkylaniline (alkyl=Me, Et) result in the formation of the new N-Grubbs-Hoveyda-type complexes 5 (NHC=SIMes, alkyl=Me), 6 (SIMes, Et), 7 (IPr, Me), 8 (SIPr, Me), and 9 (SIPr, Et) with N-chelating benzylidene ligands in yields of 50-75 %. Compared to their respective, conventional, O-Grubbs-Hoveyda complexes, the new complexes are characterized by fast catalyst activation, which translates into fast and efficient ring-closing metathesis (RCM) reactivity. Catalyst loadings of 15-150 ppm (0.0015-0.015 mol %) are sufficient for the conversion of a wide range of diolefinic substrates into the respective RCM products after 15 min at 50 °C in toluene; compounds 8 and 9 are the most catalytically active complexes. The use of complex 8 in RCM reactions enables the formation of N-protected 2,5-dihydropyrroles with turnover numbers (TONs) of up to 58 000 and turnover frequencies (TOFs) of up to 232 000 h-1; the use of the N-protected 1,2,3,6-tetrahydropyridines proceeds with TONs of up to 37 000 and TOFs of up to 147 000 h-1; and the use of the N-protected 2,3,6,7-tetrahydroazepines proceeds with TONs of up to 19 000 and TOFs of up to 76 000 h-1, with yields for these reactions ranging from 83-92 %. The tortoise and the hare: The use of diphenylalkylamino-based instead of phenyldialkylamino-based styrenes (see figure) leads to rapidly initiating precatalysts that enable very fast ring-closing metathesis reactions with turnover numbers of up to 58 000 and turnover frequencies of up to 232 000 h-1. Copyright
